Duct-work is very prevalent in most residential and commercial establishments. It is used to convey heated air or cooled air from a central unit, e.g. a furnace or cooling coils. Duct-work is also used to convey air from individual rooms back to the central unit. Fumes from a generating source are conveyed by duct-work to the atmosphere or an air treating facility. For example, restaurants have hoods and duct-work to convey cooking fumes to the outside. Industrial establishments have duct-work for the above discussed air conditioning purposes as well as for the safe removal of gases and particulates from processing operations. Individual ducts, which collectively form the duct-work, can extend for several feet and can make one or more bends.
In most all instances, ducts eventually need to be cleaned inside. Various particulates accumulate over time. Those particulates can be dislodged and forced into a room to cause carpet, wall and fabric soiling. Bacteria can grow inside duct-work under certain conditions. This, of course, can pose a health concern.
Various means have been used to clean duct-work. Ideally, the duct-work is accessed at one spot and the full length of a duct cleaned in a single operation. Cleaning devices have been designed for this purpose. One commercially used device includes a cleaning head attached to a vacuum hose. The cleaning head has a power driven rotary brush. It is driven by a shaft which leads from a remote power source, through the vacuum hose and to the cleaning head. The cleaning head with its rotary brush and vacuum hose can be forced to travel through the duct-work, including around several bends. Necessarily, the shaft from the power source and the vacuum hose are flexible and can be forced around duct bends. The rotary brush on the cleaning head rotates as it moves through the duct-work. Debris is loosened and vacuumed away. The known devices have had limited success.
It has been found, however, that there are problems associated with known cleaning head systems of the type described above. Initially, it is difficult to gain access to the interior of some duct-works without having to cut an excessively large hole in one of the ducts. As readily imagined any hole must be able to accommodate the greatest cross dimension of the cleaning head, specifically the attached rotary brush. Additionally, the rotary brush and vacuum hose must work in concert. Any debris knocked loose by the brush must be immediately sucked into the vacuum hose before it settles back onto a wall of the duct. Proximate positioning of the rotary brush and vacuum hose end is important. However, known rotary brushes have a very dense set of bristles. The rotating bristles effectively block free access to the vacuum hose end.
There has now been developed a rotary brush which is useful in cleaning the interiors of duct-work. The brush solves many problems associated with known brushes for this particular use.